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sciencehabit writes "The ancestor of all placental mammals—the diverse lineage that includes almost all species of mammals living today, including humans—was a tiny, furry-tailed creature that evolved shortly after the dinosaurs disappeared, a new study suggests. The hypothetical creature, not found in the fossil record but inferred from it, probably was a tree-climbing, insect-eating mammal that weighed between 6 and 245 grams—somewhere between a small shrew and a mid-sized rat. It was furry, had a long tail, gave birth to a single young, and had a complex brain with a large lobe for interpreting smells and a corpus callosum, the bundle of nerve fibers that connects the left and right hemispheres of the brain. The period following the dinosaur die-offs could be considered a 'big bang' of mammalian diversification, with species representing as many as 10 major groups of placentals appearing within a 200,000-year interval."

Well you gota look at it like this. The hawk has to eat too, and while things did not work out so well for the mouse his alternative like fate was not better for him. I mean he would have died slowly having one or more of his limbs crushed in trap. After which he would have been buried so deep in a landfill lack of oxygen would likely even prevent most microbes from making use of him for decades.

It might not have gone how the guy hoped but he still better served nature.

How is the different than anything else in evolutionary theory. No actual observational science, a couple of fossils here and there, no soft tissue to examine. Then bang, an possible/probable ancestral relationship is declared by somebody -- often discarded later due to other discoveries. It is what it is and will always be unless you manage to make a time machine.

"The hypothetical creature, not found in the fossil record but inferred from it, probably was " doesn't sound very much like 'stated as a fact' to me. TFT might be misleading but beyond that, the appropriate care in phrasing seems to be in use.

No, but it is designed to illicit recitation as fact later. In very short order, you will have "scientists" who state "All Mamals evolved from a single rodent" as a fact, and it will be place in Textbooks as a "fact" and so on. The fact that in the original source it is clearly hypothetical bullshit is irrelevant. Shit like this should NEVER be published as "science". It isn't "science"... yet.

How do you test the hypothosis that there is such a thing like this "rodent" creature from a few hundred million years ago existed. Either you have a fossil you can point to that "might" be this creature, or you don't (which is THIS case).

This is the problem with untestable hypothosis being introduced as "science", and it is no different than trying to create a hypothosis to test against the idea of a diety. None. Except for the fact that it is "sciency".

Exactly what my point is. It isn't what was said, it was what was said will be misconstrued as fact at some point down the road. This kind of "reporting" reflects poorly on true "science". This is nothing more than Psuedo-Science at this point.

Technically what we'll have is a good snapshot of current genomic diversity, from which we can infer the ancestry of that snapshot. We have some pretty good inferential methods, but each and every phylogeny that you see is simply a hypothesis of evolutionary relationships.

It's seems obvious to me that is what he meant, it also seems obvious to me you meant "observations" not "facts". A "fact" is an absolute truth only within an axiomatic system, science is not an axiomatic system. A "scientific fact" is a rigously tested theory that has no known conflict with observation.

Most things in science are Theories - they are the best possible explanation for what we have observed in a verifiable test. Scientific facts are either necessarily vague or very dependent on space and time. There is also the Mathematical Proof in exact sciences.

to date no other theory has been put forward that can offer a better explanation of all the known data.

That's how science works...so until a more plausible theory shows up, evolution is where we are at.

That's actually false. The Flying Spaghetti Monster and Catholic Christian religions both have equally good or better explanations, that amount to "God plays little tricks on ya, for yer own damn good!". If you posit that an omnipotent deity exists, then nothing else is really provable scientifically, unle

How is the different than anything else in evolutionary theory. No actual observational science, a couple of fossils here and there, no soft tissue to examine. Then bang, an possible/probable ancestral relationship is declared by somebody -- often discarded later due to other discoveries. It is what it is and will always be unless you manage to make a time machine.

An enormous catalogue of fossil history, geo distribution of species also provides massive evidence especially in recently observable separators such as archipelagos, the bounty genetic evidence, the ability to recreate observable evolution in our timescale on the bacterial level and our ability to force changes through selective breeding all combine to provide an irrefutable level of evidence. Each of these fields could also be used to disprove evolution if not for the fact that no reliable evidence contr

Depends on your definition of "evolution". If you mean "random mutation and natural selection", or a more-recent, nuanced version on that, there is not only extensive evidence against that as a sole causal factor, it is provably not the case.

How do we know design is a factor when speaking to the scope of biological organisms, and provably so? Because we did it ourselves, through genetic engineering.

I understand you likely don't accept that genetic engineering -also- happened previous to the 20'th century,

..... your notion of "evolution" is not merely of an indeterminate scientific status, it is provably false.

Interesting... so go ahead and disprove it. Please provide hard, testable or otherwise provable facts and not mere goofy wordplay. Are we talking proof such as finding large mammalian fossils in Ordovician or even pre Cambrian rock strata? That would do it. Or perhaps when you assert things like pre 20th century genetic engineering. Are you going to produce fingerprint signatures left behind by genetic engineers on existing modern animals? I'm eagerly awaiting the inevitable disappointment?

As stated, if your notion of "evolution" is as a scientific theory explaining all physical characteristics of biology, a set which includes organisms after 1951, it is directly false as a theory.

And regarding fingerprints and such, no, that would be a test of a -limited subset- of biology, irrelevant to a statement about evolution that is intended to apply (as most scientific theories attempt) to -all- biology, and I already stated my position on that subset is that it is untestable. We are at a point much

As stated, if your notion of "evolution" is as a scientific theory explaining all physical characteristics of biology, a set which includes organisms after 1951, it is directly false as a theory.

Citation needed. So the overwhelming concensus of the worldwide community based on an undeniable array of evidence is false because of what... I'm still waiting for something with some form of refutation and not just gassy wordplay.

.... I already stated my position on that subset is that it is untestable.

With respect to your design argument for which you refuse to provide a shred of evidence.... “That which can be asserted without evidence, can be dismissed without evidence.” – Christopher Hitchens.

We are at a point much like the situation regarding the Copenhagen and Everett interpretations of quantum mechanics--which is "true" is indeterminate as the same observables support either interpretation, and there is no presently test by which to demonstrate one correct "versus" the other.

You can observe changes of allele frequencies and phenotype frequencies in a population over time, and they do.

Also, as the TFS (and I'm assuming TFA) says "The hypothetical creature", not theoretical, not definitive, hypothentical. Evolutionary science makes it clear that all cladograms are hypothesis, if you bother looking at it from more than a surface level.

As for observation and predictability - it's hard to make predictions with evolution, but it has

Well, yes, the headline is misleading, but it's also a bit more than a "possible" ancestor.

The researchers in the study wanted to create a better phylogenetic reconstruction of the evolution of mammals than had been previously accomplished, to resolve whether divergence of placental mammals from non-plancental mammals (egg-laying / marsupials) occurred before or after the extinction of the Dinosaurs (the K-T boundary), and also to make predictions of the biology of that last common ancestor. Previous phylogenetic reconstructions had been done with molecular data (DNA or protein sequences), but molecular data is limited to extant species and makes a lot of assumptions about the rates of changes in DNA that get more unreliable the further back in time you go. This study combined molecular data with character traits they call 'phenomic' characters - from the paper: "4541 phenomic characters de novo for 86 fossil and living species." The resulting matrix of traits, both molecular and character, was used to generate a tree based on maximum parsimony [wikipedia.org] - a method which minimizes the number of trait changes over time when building a tree. This resulted in a single, highest scoring tree predicting the evolution of these species and the changes in their traits over time. The resulting tree is then "clocked" (called 'time-calibration in the paper) to known rates of evolution for the molecular data (good for recent divergence of species) and by fossil data to give time ranges for the deeper sections of the tree. This last part is key, as you cannot get molecular data from fossils, and fossils allow you to map the existence of certain traits within a group to a certain point in the history of these organisms.

The result is a time-range in which the last common ancestor between placental and NON-placental mammals must have lived, given the data provided and the parsimony criterion. As the tree makes claims about when the phenomic characters evolved or were lost, it also predicts which phenomic characters the last common ancestor had.

The characteristics of the first placental are not really controversial. The real news here is that a lot of the work on placentals and eutherians is wrong and must be re-evaluated. Granted, a lot of the placental work was already merely tentative. Molecular phylogenetics estimates had placentals appearing about 105 Mya, This new work ignores the molecular results and comes up with a later date. From what I can see, dating of the relevant available fossils is equivocal.

Also curious is that according to this interpretation, the ancestral afrotherian (elephants, aardvarks, manatees, etc.) originated in South America and somehow migrated across the then 1000-mile ocean to Africa. Prepare for further revision.

No it doesn't. You think you are actually able to reason with creationists but this is not the case. Creationist operate on the belief level, outside of reason, thus it does not matter how good the scientific facts are. Write creationists off and go on with your life.

You do realize this is exactly how science works, right? You look at the world, then you come up with a hypothesis which has conclusions (like this creature). You then test the conclusions (in this case look for it in the fossil record). If you find it, you can move to the theory stage. If a competing hypothesis (yes those exist) finds theirs instead, they get to move on to the theory stage.

Today's education system even impacts/. when a "hypothetical" creature "not found" in the fossil record, but "inferred" by it, is now put forth as a revelation as to the origin of all mamals, including humans.

By not being found in the fossil record, we have no concrete evidence. By being inferred, we have reasoned it's existence. That makes the use of the term "revealed" quite correct, as that is exactly the same process early man used to determine their various deities.

Science deals with observation, not truth. If you'd read a little, you might get to the things that were being observed.

You're clearly interested in some sort of truth, which is a different matter entirely. Science will never offer you that; our boundaries of truth are whatever our instruments can tell us. Which is a lot more than any religious education has ever produced, but I won't hold a grudge.

Case in point: I can give 100 people the same 1 frame from the same movie that none of them (or I) have seen before and ask them to tell me the plot and I'll get 100 different answers

Then you're doing it wrong. Give them each a different frame from a different point in the movie, and then let them get together to put them in a hopefully coherent whole. A few frames will be out of order, or perhaps reversed or upside down, but you'll end up with a pretty good approximation of the plot. We don't have j

If it lays eggs then it's not a placental mammal (is that right? I think that's right).

It is difficult to be sure about anything for this odd creature. It has venom (for males only), electric field sensitivity, 5 pair of sexual chromosomes... If nature proceeds from an intelligent design, then the creating intelligence was probably intoxicated the day it created ornithorhynchus

from the wiki on platypus :
"The platypus and other monotremes were very poorly understood, and some of the 19th century myths that grew up around themâ"for example, that the monotremes were "inferior" or quasireptilianâ"still endure.[60] In 1947, William King Gregory theorised that placental mammals and marsupials may have diverged earlier, and a subsequent branching divided the monotremes and marsupials, but later research and fossil discoveries have suggested this is incorrect.[60][61] In fact,

This is what we mean when we say that science makes predictions. Remember tiktaalik? Based on the rest of the fossil record and based on geology, scientists predicted that a certain fossil of a certain creature would be found in a certain kind of rock at a certain depth. It took them several years of digging but they found that fossil at that depth in that rock. Science made a specific prediction and it came true.

Likewise, based on the rest of the fossil record we believe this creature must have existed. We might be able to predict where we would find fossils for it.

"The hypothetical creature, not found in the fossil record but inferred from it..." I know this is/., but c'mon.

Perhaps if you actually read the study. They examined, among many other things, the size and shape of all mammals as changed over time. By examining the emergence of genes, traits and other patterns and their geographical distribution allowed them to build a new family tree of placental mammals. They then just followed all the clues back up the tree of species until they found all the common traits converging on a single creature. It was previously believed to be a type of vole. The article is more abou

had a complex brain with a large lobe for interpreting smells and a corpus callosum, the bundle of... etc

Somehow my brain kept interpreting this akin to the concerto for smells and a corpus callosum, interpreted by the brain rather than a large lobe, to interpret the smells, and a corpus callosum; the later is the bundle of... I reckon its something to do with commas and the mixed nature of details: purpose (for smell) with details of structure (the bundle etc).

We all know the Earth is only 6000 years old and that humans were created by God in his image. At least that's what Fox News and the 700 Club tell me. Why should I believe science when I have Fox News to tell me the truth?

Consider a hypothetical "evolutionary space", which has room for a certain number of instances of traits. For example, an ecosystem might be able to support 5k big awesome carnivores, or 20k small lame ones, or some ratio of the two. Now imagine such a space as it stood right near the end of the dinosaurs. When the dinosaurs were around, the "space" was full, the only evolutionary "improvements" that could take place were ones that were super effective. Then poof! dinos are gone; a lot more space is ava